When he assumed his new position on February 24, 1931, Athenagoras was faced with the task of bringing unity and harmony to a diocese that was racked with dissension between Royalists and Venizelists who had virtually divided the country into independent dioceses. To correct this he centralized the eccelesiastical administration in the Archdiocesean offices with all other bishops serving as auxiliaries, appointed to assist the archbishop, without dioceses and administrative rights of their own. He actively worked with his communities to facilitate these reforms. He expanded the work of the clergy-laity congresses and founded the Holy Cross School of Theology. His capable leadership allowed him to withstand the early opposition he faced and eventually gain the love and devotion of his flock.

Ecumenical Patriarch Athenagoras I (left) with Pope Paul VI

Patriarchate

On November 1, 1948, Athenagoras was elected Patriarch of Constantinople, and was flown to Istanbul in the personal airplane of then-president Harry Truman. As patriarch, he was actively involved with the World Council of Churches and improving relations with the Pope. His long reign ended with his died in Istanbul on July 7, 1972.

His 1964 meeting with Pope Paul VI in Jerusalem led to the mutual lifting of the Bulls of Excommunication that resulted in the Great Schism of 1054. This was a significant step towards restoring communion between Rome and Constantinople. It produced the Catholic-Orthodox Joint Declaration of 1965, which was publicly read on December 7, 1965, simultaneously at a public meeting of the Second Vatican Council in Rome and at a special ceremony in Istanbul. The declaration did not end the schism, but showed a desire for greater reconciliation between the two churches. Nevertheless, not all Orthodox shared this sentiment, resulting in one hierarch, Metropolitan Philaret, writing a response to the patriarch that same year.